Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2015)
© 2016 Elsevier B.V.The most established route to create a laser-based neutron source is by employing laser accelerated, low atomic-number ions in fusion reactions. In addition to the high reaction cross-sections at moderate energies of the projectile ions, the anisotropy in neutron emission is another important feature of beam-fusion reactions. Using a simple numerical model based on neutron generation in a pitcher-catcher scenario, anisotropy in neutron emission was studied for the deuterium-deuterium fusion reaction. Simulation results are consistent with the narrow-divergence (∼70° full width at half maximum) neutron beam recently served in an experiment employing multi-MeV deuteron beams of narrow divergence (up to 30° FWHM, depending on the ion energy) accelerated by a sub-petawatt laser pulse from thin deuterated plastic foils via the Target Normal Sheath Acceleration mechanism. By varying the input ion beam parameters, simulations show that a further improvement in the neutron beam directionality (i.e. reduction in the beam divergence) can be obtained by increasing the projectile ion beam temperature and cut-off energy, as expected from interactions employing higher power lasers at upcoming facilities.
Investigation of the solid-liquid phase transition of carbon at 150 GPa with spectrally resolved X-ray scattering
HIGH ENERGY DENSITY PHYSICS 14 (2015) 38-43
Evidence of locally enhanced target heating due to instabilities of counter-streaming fast electron beams
PHYSICS OF PLASMAS 22 (2015) ARTN 020701
NATURE PHOTONICS 9 (2015) 274-279
ASTRONOMY & ASTROPHYSICS 576 (2015) ARTN A80
ASTROPARTICLE PHYSICS 66 (2015) 39-52
Development of a general analysis and unfolding scheme and its application to measure the energy spectrum of atmospheric neutrinos with IceCube: IceCube Collaboration.
The European physical journal. C, Particles and fields 75 (2015) 116-
We present the development and application of a generic analysis scheme for the measurement of neutrino spectra with the IceCube detector. This scheme is based on regularized unfolding, preceded by an event selection which uses a Minimum Redundancy Maximum Relevance algorithm to select the relevant variables and a random forest for the classification of events. The analysis has been developed using IceCube data from the 59-string configuration of the detector. 27,771 neutrino candidates were detected in 346 days of livetime. A rejection of 99.9999 % of the atmospheric muon background is achieved. The energy spectrum of the atmospheric neutrino flux is obtained using the TRUEE unfolding program. The unfolded spectrum of atmospheric muon neutrinos covers an energy range from 100 GeV to 1 PeV. Compared to the previous measurement using the detector in the 40-string configuration, the analysis presented here, extends the upper end of the atmospheric neutrino spectrum by more than a factor of two, reaching an energy region that has not been previously accessed by spectral measurements.
Physical review letters 115 (2015) 081102-
Results from the IceCube Neutrino Observatory have recently provided compelling evidence for the existence of a high energy astrophysical neutrino flux utilizing a dominantly Southern Hemisphere data set consisting primarily of ν(e) and ν(τ) charged-current and neutral-current (cascade) neutrino interactions. In the analysis presented here, a data sample of approximately 35,000 muon neutrinos from the Northern sky is extracted from data taken during 659.5 days of live time recorded between May 2010 and May 2012. While this sample is composed primarily of neutrinos produced by cosmic ray interactions in Earth's atmosphere, the highest energy events are inconsistent with a hypothesis of solely terrestrial origin at 3.7σ significance. These neutrinos can, however, be explained by an astrophysical flux per neutrino flavor at a level of Φ(E(ν))=9.9(-3.4)(+3.9)×10(-19) GeV(-1) cm(-2) sr(-1) s(-1)(E(ν)/100 TeV(-2), consistent with IceCube's Southern-Hemisphere-dominated result. Additionally, a fit for an astrophysical flux with an arbitrary spectral index is performed. We find a spectral index of 2.2(-0.2)(+0.2), which is also in good agreement with the Southern Hemisphere result.
Determining neutrino oscillation parameters from atmospheric muon neutrino disappearance with three years of IceCube DeepCore data
PHYSICAL REVIEW D 91 (2015) ARTN 072004
JOURNAL OF PLASMA PHYSICS 81 (2015) ARTN 305810104
ASTROPHYSICAL JOURNAL 807 (2015) ARTN 46
PLASMA PHYSICS AND CONTROLLED FUSION 57 (2015) ARTN 014014
Identification of globular cluster stars in RAVE data - I. Application to stellar parameter calibration
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 451 (2015) 1229-1246
EUROPEAN PHYSICAL JOURNAL C 75 (2015) ARTN 20
Observation of magnetic field generation via the Weibel instability in interpenetrating plasma flows
NATURE PHYSICS 11 (2015) 173-176
ASTROPHYSICAL JOURNAL 806 (2015) ARTN 117
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 448 (2015) 3391-3404
The Gaia-ESO Survey: Empirical determination of the precision of stellar radial velocities and projected rotation velocities
ASTRONOMY & ASTROPHYSICS 580 (2015) ARTN A75
INEFFICIENT DRIVING OF BULK TURBULENCE BY ACTIVE GALACTIC NUCLEI IN A HYDRODYNAMIC MODEL OF THE INTRACLUSTER MEDIUM
ASTROPHYSICAL JOURNAL 815 (2015) ARTN 41